Guillotine sharpener

ABSTRACT

A motor driven guillotine sharpener having a body in which at least a pair of grinding wheels are mounted for rotation about parallel shafts, the body being adapted to lie on the guillotine bed and means ensuring that the angle of the grinding wheels, when the deivce is on the bed, is the required bevel angle of the guillotine blade to be sharpened.

I Umted States Patent 1 [111 3, Williams [45 July 17, 1973 GUILLOTINESHARPENER 2,417,373 3 1947 Morrison et al. .1 51/249 [75] Inventor:Patrick Robert Williams, Mount Ehza Victoria Austraha PrimaryExaminerlamcs L Jones, Jr. A signee: Temtool Pty. Limited, Victoria,Attorney-H0lman & Stern Australia [22] Filed: June 28, 1971 21 Appl.No.: 157,383 [571 ABSTRACT Q A motor driven guillotine sharpener havinga body in [52] US. Cl. 51/249 hi h t l t; a pair of grinding wheels aremounted for [51] hit. Cl. B241) 19/ rotation about parallel shafts, thebody being adapted [58] Field of Search 51/246, 250, 173, t lie on theguillotine bed and means ensuring that the 128 angle of the grindingwheels, when the deivce is on the bed, is the required bevel angle ofthe guillotine blade [56] References Cited to be sharpened.

UNITED STATES PATENTS 3,381,417 5/1968 Eckstein 51/128 X 5 Claims, 5Drawing Figures PATENTE JUL 1 7 m5 BACKGROUND OF THE INVENTION PRIORTECHNIQUES Industrial guillotines and particularly those used forcutting large stacks of paper or card stock need to be sharpenedregularly and to the present time it has been usual to remove the bladefrom the guillotine for sharpening. This has been time consuming and insome operations it has meant that a guillotine has been nonoperative fora period of each day. Where very regular sharpening is necessary, itwould normally be essential to have at least two blades for a guillotineso that as soon as a blade is removed, it can be replaced with asharpened blade and the removed blade later sharpened.

OBJECTS AND SUMMARY OF THE- INVENTION The object of the presentinvention is to provide an apparatus whereby a guillotine blade can besharpened while still on the guillotine and which apparatus can be usedby a relatively unskilled person to obtain consistent results and goodsharpening.

The invention includes a guillotine sharpener having a body, a motorlocated within the body, at least two grinding wheels externally of thebody, each grinding wheel being mounted for rotation about a shaftextending from the body, the axes of the shafts being parallel, a drivebetween the motor and the grinding wheels, the body having surfaces suchthat when on a bed of the guillotine, the grinding wheels are at anangle to the bed close to the required sharpening angle, and means onthe body whereby the angle of the body relative to thebed, and hence theangle of the grinding wheels relative to the guillotine blade can bevaried.

Preferably, the grinding wheels extend from one side of the body at anangle which may be of the order of 30 when the base of the body isresting on the bed and the adjustment means may comprise a verticalshaft passing through the body so as to partially rotate the body abouta downwardly extending portion between the grinding wheels and theadjustment means and in one particular form, the length of this shaftmay be such as to locate the grinding wheels at an angle ofapproximately 16 to the vertical and when fully extended.

An indicator means may be provided on the body whereby an indication ofthe pressure of contact of the wheels with the blade to be sharpened canbe ascertained.

In order that the invention may be more readily understood and put intopractice we shall describe one specific form of the device. This'devicewill be described in relation to the accompanying drawings in which: I 7

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a front view of the device;

FIG. 2 is a plan view;

FIG. 3 is a side elevation;

FIG. 4 shows an orientation of the device before the final adjustmentfor grinding occurs, and

FIG. 5 shows the device when grinding.

DETAILED DESCRIPTION OF THE INVENTION Basically the device includes abody 1 which may be a hollow casting and mounted within the body is anelectric motor 2, the shaft of which extends to front 3 of the device.The drive from the motor 2 is by means of a belt 4 which passes under apair of idler pulleys 5 and around pulleys 6 which extend through thefront face 3 onto the outer ends of which are attached grinding wheels7. In the preferred form of the device, the grinding wheels may beapproximately 3 inches in diameter and their axes may be spaced byapproximately 9 inches. If preferred, the belt 4 may be ribbed and theshaft of themotor 2 and the pulleys 6 may be formed to engage with theribs on the belt to thus give positive driving between the motor and thepulleys.

The lower cover of the body 1 carries a downward extension 9 which liesacross a substantial portion of the width of the device.

Located in a tapped aperture in the rear of the body is a threaded shaft10 having a finger grip portion 11 at its outer end, a lock nut 12 abovethe portion of the body through which it passes and a foot 13 beneaththe body.

Mounted on top 14 of the body is a switch 15 and a load meter 16 whichload meter gives an indication of the current drawn by the motor.

In operation, the guillotine clamp is held in its up position either bymeans of a control on the guillotine or by placing a stack of paperunder the clamp behind the blade and blade 17 is brought downwardlyuntil it is located approximately We to 2 inches from the guillotinebed. This will bring the blade into a position approximately centrallyof the grinding wheels 7. It will be appreciated that guillotine bladesnormally lie at an angle to the bed but as they become close to the bed,this angle lessens and the angle when the blade is at approximately 1.5to 2 inches from the bed has no effect on the operation of the sharpenerexcept that the blade at one end of movement of the sharpener will liehigher on the grinding wheels than at the other end.

The finger grip portion 11 of the shaft 10 is then adjusted until thegrinding wheels are at the same angle as the bevel of the blade and thiscan be checked by chalking the bevel and then moving the device acrossthe blade to see whether chalk is removed. This position is asillustrated in FIG. 4 of the drawings. Once this location has beenachieved, the angle of the grinding wheels to the vertical is increasedby rotating the threaded shaft 10 by a predetermined number of times(say six) so that the grinding wheels are then located at an angle tothe body of the bevel and then contact only occurs adjacent the cuttingedge of the blade. This position is as illustrated in FIG. 5 of thedrawings. At the same time, the lock nut 12 is tightened and the tool isthen set for use with the particular guillotine and, if it is to be usedonly with the particular guillotine, then the adjustment should not needre-setting.

The sharpener is then brought into light contact with the blade at oneend, the motor is switched on and the sharpener running on the extension9 and the foot 13 is moved across the blade. The pressure of contact iscontrolled by maintaining a constant reading on the load meter 16 and inone specific form of the invention, there is used a pressure such thatthe motor draws 0.5 AMPS above the non-load reading. When the sharpenerreaches the other end of the blade, the motor is shut-off. The blade canthen be checked for sharpness and, if necessary, the contact andmovement of the sharpener repeated, although there will be no need toadjust the device.

Some guillotine blades are formed with a microbevel at an angle to themain bevel of the blade and if this is the case, the grinding wheels 6are located as acurately as possible against the microbevel rather thanthe bevel itself and a very slight increase in angle is obtained byrotating threaded shaft 10. The degree of increase may be approximatelyone-sixth the degree which is normally used any one time of the shaft10.

If, after re-sharpening, the blade leaves uneven marks on the paperstack, these are caused by scoring on the back of the blade and have norelation to the sharpening. Often however, the scored metal can beremoved by sharpening the blades slightly more.

If this scoring has occured from the blade contacting the back of theclamp or from other external causes the scoring must be removed byhoning or polishing the back of the blade either in or out of themachine.

It may be seen that the sharpening device of the present inventionprovides a rapid and accurate way of sharpening guillotine blades whilestill in position thus overcoming a large percentage of the normalexpected downtime for such guillotines.

I claim:

1. A guillotine sharpener including a body, a motor located in the body,at least two grinding wheels externally of the body each grinding wheelbeing mounted for rotation about a shaft extending from the body, theaxes of the shafts being parallel, a drive between the motor and thegrinding wheels, the body having surfaces such that when on a bed of theguillotine, the grinding wheels are at an angle to the bed close to therequired sharpening angle, and means on the body whereby the angle ofthe body relative to the bed, and hence the angle of the grinding wheelsrelative to the guillotine blade can be varied.

2. The guillotine sharpener as claimed in claim I wherein the grindingwheels extend from one side of the body and in which a threaded shaftextends through the body adjacent the other side, with the movement ofthe shaft altering the angle of the grinding wheels relative to theguillotine bed.

3. The guillotine sharpener as claimed in claim 2 wherein there is anextension on the underside of the body between the grinding wheels andthe shaft, adjacent the grinding wheels, with the extension lying acrossa substantial part of the width of the base.

4. The guillotine sharpener as claimed in claim 1 wherein the are drivenby means of a continuous belt.

5. The guillotine sharpener as claimed in claim 1 in which said motor isan electric motor and including means to measure the current drawn bythe motor to control pressure of the grinding wheels.

1. A guillotine sharpener including a body, a motor located in the body,at least two grinding wheels externally of the body each grinding wheelbeing mounted for rotation about a shaft extending from the body, theaxes of the shafts being parallel, a drive between the motor and thegrinding wheels, the body having surfaces such that when on a bed of theguillotine, the grinding wheels are at an angle to the bed close to therequired sharpening angle, and means on the body whereby the angle ofthe body relative to the bed, and hence the angle of the grinding wheelsrelative to the guillotine blade can be varied.
 2. The guillotinesharpener as claimed in claim 1 wherein the grinding wheels extend fromone side of the body and in which a threaded shaft extends through thebody adjacent the other side, with the movement of the shaft alteringthe angle of the grinding wheels relative to the guillotine bed.
 3. Theguillotine sharpener as claimed in claim 2 wherein there is an extensionon the underside of the body between the grinding wheels and the shaft,adjacent the grinding wheels, with the extension lying across asubstantial part of the width of the base.
 4. The guillotine sharpeneras claimed in claim 1 wherein the are driven by means of a continuousbelt.
 5. The guillotine sharpener as claimed in claim 1 in which saidmotor is an electric motor and including means to measure the currentdrawn by the motor to control pressure of the grinding wheels.